Process of producing solutions for spinning artificial threads and the like.



UNITED STATES PATENT OFFICE.

RUDOLF LINKMEYER, OF BREE EN, GERMANY.

rnocnss or PRODUCING SOLUTIONS FOR SPINNING ARTIFICIAL 'rimnans AND .THELIKE. r

No Drawing.

To all whom it may concern:

Be it known that I, RUooLr LINKMEYER, a subject of the German Emperor,and residing at Bremen, Germany, have invented. a certain new and usefulImproved Process of Producing Solutions for Spinning Artificial Threadsand the Like, of which the following is a specification.

The subject-matterof my invention is an improved process of producingdurable so lutions for spinning artificial threads and the like. I

It has been found that cupro-ammonium cellulose solutions, which onaccount of their sensitiveness to heat can only be produced andpreserved at a low temperature, acquire a high degree of permanence whenother carbo-hydrates are incorporatedin them.

They then stand, a temperature of 30 to 40 C. without injury andconsequently can be preserved without being cooled. In addition, theproducts produced are exceedingly waterproof and elastic. Further, finethreads obtained therefrom do not adhere to ether and have an excellentsilky gloss.

y invention consists in mixing carbo-hydrates with cupro-ammoniumcellulose solutions obtained in the usual manner.

The solutions obtained are very simply worked up, for the structuresformed from them become, strange to say, perfectly transparent when theammonia simply evaporates 1n the air and they maintain this valuableproperty during all the subsequent operations. Similar structures couldbe obtained heretofore from pure cupro-ammonium cellulose solutions onlyby coagulation by means of alkalies, but the products obtainableaccording to my invention are superior to these also in strengthandelasticity. Moreover they can be dried, without previously removing thecopper, without their transparency being impaired, whereas the productsobtained in known manner from pure cellulose solutions would, under likeconditions, form non-transparent, brittle masses. This circumstance isof considerable importance; as the manufacture of artificial threads,for example, requires after the spinning operation a series ofoperations, which heretofore had to be erformed directly after thespinning, an under.conditions when the threads are particularlysensitive. If one proceeds according to the present new process, on thecon- Specification of Letters Patent.

consequently trary,.-it'is' quite possible to work up the crude threadsbefore or after the first drying process; for, as follows from theabove, these threadsare very particularly suitable for being worked upafter being dried in conse-' guence of their tensile strength andelasicity.

Most of the carbo-hydrates can be employed in my new process; Very goodresults' are obtained with hexoses di-saccharids or polysaccharids byemploying them in proportions of about 25% by weight of the cellulose.

Patented J an. 4, 1910. Application filed March 8, 1909. Serial No.482,001.

Example A cupro-ammonium cellulose solution having 7% cellulose isprepared in a kneading-machine in one of the knownways, a small quantityof glycerin, one half to one per cent. of the weight of the cellulosebeing mixed with the ammonia for the purpose of increasin the solubilityof the cupric hydrate. lo more-ammonia, z. e. pure NH is then necessarythan is equal to the weight of the cellulose. Potato syrup, glucose, tothe amount of about 35% of the weight of the cellulose is addedgradually to the solution, which is obtained in a short time without anycooling, whereupon the whole mass is kneaded for some time longer. Themass is then ready for use.

If importance is attached to it, before working it up into threads andthe like, aconsiderable quantity of ammonia may be removed from the massby simply heating it without any precipitation having to be feared.While the ammonia is caused to evaporate, the solution behaves quitediflerently from pure cupro-ammonium cellulose solution which, as soonas its percentage of ammonia begins to fall below 0 grams per liter, isno longer able to keep in solution the entire quantity of cellulose andas the ammonia continues to escape is converted into a rigid, brittleand non-transparent, ultramarine blue mass. In contradistinction tothis, under like conditions solid precipitates are not precipitated atall from the new solutions; on the contrary the masses remain until thelast homogeneous solutions,-

which only increase in toughness in the mass as ammonia is evaporatedfrom them. When the ammonia has entirely escaped caoutchouc-like, butperfectly transparent roducts remain behind which, when ried, finallyharden but keep their transparency. Having regard to the1r behavior whenthe larly suitable for many kinds of usetul pur poses,- since-tl1ey canbe 'coagulated after heing shaped in a simple manner without any furthermeans. They'may, however, also be coagulated by means of the usualcoagulat1on baths such as are used for pure cellulose solutions.

I claim 1. The 'process of-profiucing durable solutions for spinningartificial threads and the like, which 'comprises mixing a sugar withcuproammonium cellulose, and retaining the sugar in the solution withouteflecting the reduction of'the cu tic-hydrate of the onpro ammonium celulose solution thereby alkali; y 2. The process of producing durablesolutions for spinning artificial threads, which .comprises adding to acupro-ammonium solution about 35% by weight of its cellulose content, ofsugar and retaining the sugar in the solution withouteflecting thereduction of the cu ric-hydrate of the cupro-ammonium celluose-solution:

In testimony when of, :I a-fiix my signature in the presence of twowitnesses.

RU'DQLF LINKMEYER. Witnesses MARIE MAHNKmI, FERDINAND avoiling thenecessity of treatment with

